内旋转(internal rotation)
参考答案:
胎头到达中骨盆为适应骨盆纵轴而旋转,使其矢状缝与中骨盆及骨盆出口前后径相一致的动作称内旋转。
—Can you shoot that bird at the top of the tree?
—No, it's out of ______.[ ]
A. range
B. reach
C. control
D. distance
热力除氧的原理是什么?